The Powder Coating Process

The powder coating process has several states. Importantly, the pretreatment of aluminium extrusions ensures the highest quality paint finishes on the extrusion or component.

Information about the powder coating process.

The powder coating process and pre-treatment requires the best possible pretreatment of sections to make sure that the powder has best possible adhesion onto the metal. A quality paint finish comes as a result of the maximum adhesion of the powder. Therefore effective pretreatment helps to ensure this happens.

Cleaning.

This is the first stage of the pre-treatment process and important. It is imperative that the painted component gets thoroughly cleaned at this stage. Dirty material results in a lower quality paint finish.

A typical way of cleaning the component is with the immersion cleaning process in an acid etch cleaning solution.

Rinsing

Rinsing of the components to be powder coated is carried out using a rinse typically at the same temperature as the cleaning process before. This is normally a rinse process using clean water.

Chromate Pretreatment
The chromate process is widely used in polyester powder coating and it comprises a chrome phosphate process. The chromatin process ensures the best surface is available prior to polyester powder coating.

The coating process ensures that material has the best surface treatment to attain optimum corrosion resistance and helps the bonding process of the subsequent polyester powder coating.

Second Rinse.

A second rinse follows the chromate treatment.

The Third Rinse.

This process comprises another two parts water rinse.

Final Rinsing.

This process is a demineralised water rinse.  This rinse removes all the contaminants.  The pure water rinse also ensures that the surface is absolutely clean prior to polyester powder coating.

Drying.
The drying process is relatively quick achieving a metal temperature of not exceeding 80 degrees Celcius.

Between all of the above stages sits a period of time known as the “drain zone”. The drain zone moves material for powder coating from one cleaning process to the next. At the same time, the metal remains wet enough between the stages.

Get in touch today for answers to all your questions about the painting of aluminium extrusions for the construction sector and to get a quotation.